1. Field of the Invention
The present invention relates to a method, for smooth scheduling on a periodic basis in a client-server system, an apparatus, having a scheduler embodied on a computer readable medium, and a scheduler embodied on a computer readable medium for creating a schedule, which allocate execution time slots for operation. As an example of creating a schedule, a server may determine the time slots for transmitting control instructions to a plurality of client apparatuses and creates a schedule thereby. In this case, it is required that a schedule be created so that the load in each time slot to the server does not become excessive. Furthermore, the present invention relates to a method for smooth scheduling on a periodic basis in a client-server system, an apparatus, having a scheduler embodied on a computer readable medium, and a scheduler embodied on a computer readable medium, in which an information consumer electronics server performs remote control to a particular information consumer electronics terminal, and the remote control is performed in a timing, wherein distribution of server resources in the information consumer electronics server is considered, particularly under the environment where the information consumer electronics server is connected to a plurality of information consumer electronics terminals by broadcasting or other communication network.
2. Description of Prior Art
In the case of transmitting the control instruction to a plurality of client apparatuses, the server makes a call out to the client apparatuses or the client apparatuses make a call out to the server, to establish a communication path, and thus control instructions are transmitted from the server. Conventionally, due to the high price of the client apparatus which communicates with the server, and the number of client apparatuses with which one server communicates staving at a level of one hundred odd units at most, there has not been a particular need for making an arrangement for creating a communication schedule.
Further, even in the case of making such arrangement, the arrangement has been inadequate, and the control table as shown in FIG. 15 has conventionally been used in order to control the timing of remote control, taking in consideration of the distribution of server resources. In FIG. 15, Table 1501 is a time frame control table that controls the reservation status of resources in each time frame, and Table 1502 is a table for controlling maximum values of resources that controls the maximum values of the server resources.
In FIG. 15, time slots, in which 1 day is divided into four time slots (time slot 1=00:00 to 05:59, time slot 2=06:00 to 11:59, time slot 3=12:00 to 17:59, time slot 4=18:00 to 23:59), are used as an example. Further, the cycle by which the server resources is distributed is set to 1 week (7 days). Accordingly in the example of FIG. 15, the reservation status of resources is controlled on the time frame control table 1501 based on the total of 28 time frames in relation to each time slot, wherein each day of the week is divided into four time slots. Furthermore, the respective maximum value of the server resources is controlled on the table for controlling maximum values of resources 1502 based on the total of 28 time frames in relation to each time slot, wherein each day of the week is divided into four time slots, in the same manner. In a conventional method, when an additional reservation of resources is newly made for “a time slot of a day of the week,” the method was limited to the task of confirming that the value of the corresponding time frame, in the time frame control table 1501 after reservation, does not exceed the value of the corresponding time frame of the table 1502 for controlling maximum values of resources. When the first value does not exceed the second value as above, the method then makes a determination that new addition of reservation of resources can be made, and the operation to add reservation is thereby carried out. Note that the algorithm to make the time frame control table 1501 having a uniform reservation status can be cited as an example of a conventional algorithm to determine “a time slot of a day of the week.” This algorithm determines a time frame having the smallest number of reservation status in the time frame control table 1501 as a time frame, in which addition of reservation of new resources is made.
As described above, in the environment under which the server is connected with a plurality of client apparatuses in the prior art, consideration has only been made as to how the server resources should be distributed in 1 cycle at most, that is, 1 week (7 days) in the example of FIG. 15.
However, information consumer electronics products, which are information equipment having a function to communicate with the server via a telephone line, have been provided inexpensively in recent years, the number of client apparatuses having the function to communicate with the server has increased at a faster rate, and it is predicted that the number will reach several hundreds of thousand or even a level of a few million. In addition, because the information consumer electronics products are used for a long period of time, the server apparatus needs to issue control instructions repeatedly to regularly perform function setting or the like. Consequently, in the server apparatus that communicates with a large number of client apparatuses, there exists a problem that the server apparatus is overloaded and sufficient service cannot be provided unless a communication schedule between the server apparatus and the client apparatuses is appropriately created. Further, there also exists a problem that operation of creating a schedule must be efficiently performed.
Furthermore in the prior art, when the server resource are distributed for a plurality of cycles, the operation to add reservation can only be performed to the time frame control table and to the table for controlling maximum values of resources, which are independent of each other, and accordingly, there also exists a problem that the server resources have not been effectively utilized, taking in consideration the relation among a plurality of cycles.
The method, the apparatus and the computer-program for creating a schedule to solve these problems have not been known.